Abstract: A shaft seal device according to at least one embodiment of the present disclosure includes: a plurality of thin plates arranged in a circumferential direction of a rotational shaft and each having a width in an axial direction of the rotational shaft and a seal ring including a seal mounting groove for mounting the plurality of thin plates. An inner wall of the seal mounting groove on one side in the axial direction has a groove formed along the circumferential direction, in an inner region in a radial direction of the rotational shaft.

Abstract: A valve spring includes a nitrided layer, and a core portion that is further inward than the nitrided layer. A chemical composition of the core portion consists of, in mass %, C: 0.53 to 0.59%, Si: 2.51 to 2.90%, Mn: 0.70 to 0.85%, P: 0.020% or less, S: 0.020% or less, Cr: 1.40 to 1.70%, Mo: 0.17 to 0.53%, V: 0.23 to 0.33%, Ca: 0.0001 to 0.0050%, Cu: 0.050% or less, Ni: 0.050% or less, Al: 0.0050% or less, Ti: 0.050% or less, and N: 0.0070% or less, with the balance being Fe and impurities. In the core portion, a number density of V-based precipitates having a maximum diameter ranging from 2 to 10 nm is 500 to 8000 per ?m2, and in the core portion, a numerical proportion of Ca sulfides with respect to a total number of oxide-based inclusions and sulfide-based inclusions is 0.20% or less.

Abstract: According to one embodiment, the silicon layer includes phosphorus. The buried layer is provided on the silicon layer. The stacked body is provided on the buried layer. The stacked body includes a plurality of electrode layers stacked with an insulator interposed. The semiconductor body extends in a stacking direction of the stacked body through the stacked body and through the buried layer, and includes a sidewall portion positioned at a side of the buried layer. The silicon film is provided between the buried layer and the sidewall portion of the semiconductor body. The silicon film includes silicon as a major component and further includes at least one of germanium or carbon.

Abstract: According to one embodiment, the silicon layer includes phosphorus. The buried layer is provided on the silicon layer. The stacked body is provided on the buried layer. The stacked body includes a plurality of electrode layers stacked with an insulator interposed. The semiconductor body extends in a stacking direction of the stacked body through the stacked body and through the buried layer, and includes a sidewall portion positioned at a side of the buried layer. The silicon film is provided between the buried layer and the sidewall portion of the semiconductor body. The silicon film includes silicon as a major component and further includes at least one of germanium or carbon.